Nozzle for vacuum cleaner

ABSTRACT

A nozzle for a vacuum cleaner having a hollow nozzle body having means for connecting the vacuum pipe of a vacuum cleaner to the nozzle body, the nozzle body having a vacuum pick-up opening in a side thereof which is turned away from the connecting means, the part of the opening in the side of the nozzle body being closed by an insert the outer area of which is covered by a brush cover. The insert may either be installed as a part removable from the nozzle body or as a permanent part thereof. In certain of the disclosed embodiments the bristles of the brush cover are tilted with respect to the main extent of the brush cover. The bristles may all be pointed in the same direction, as for example, in the pull direction of the vacuum nozzle. In another illustrative embodiment, a part of the bristles may be tilted in the pull direction and a part may be tilted in the push direction, so that the nozzle picks up lint, dirt and the like in both directions of its travel. The nozzle of the invention may also be pivotally connected with the vacuum pipe of a vacuum cleaner, and may include a pivotally mounted skirt which defines the vacuum area in communication with the vacuum port of the nozzle in all possible positions of tilting of the nozzle about its pivotal connection.

llnited StatesPatent 1191 Krusche 1 Sept. 10, 1974 NOZZLE FOR VACUUMCLEANER I [75] Inventor: Kurt Krusche, Frankfurt/Main,

. Germany [73] Assignee: ALLSTAR Verbrauchsgueter GmbH & Co. KG,Frankfurt/Main, Germany [22] Filed: Apr. 17, 1972 [21] Appl. No.:244,806

[30] Foreign Application Priority Data May 12, 1971 Germany 2123436 [52]US. Cl. 15/400, 15/231 [51] Int. Cl A471 9/06 [58] Field of Search15/231, 393, 398, 399, 15/400 [56] References Cited UNITED STATESPATENTS 1,068,713 7/1913 Thurman ..15 /393 2,648,863 8/1953 Darling15/231 2,793,385 5/1957 Ortega 15/400 X 3,108,310 10/1963 Allen et a1.15/373 X 3,421,171 l/1969 Tsuruzawa 15/231 UX 3,619,846 11/1971 Kruscheet a1...... 15/231 UX Primary Egcgm iner-l-larvey l-lornsby AssistantExaminer-C. K. Moore [5 7] ABSTRACT A nozzle for a vacuum cleaner havinga hollow nozzle body having means for connecting the vacuum pipe of avacuum cleaner to the nozzle body, the nozzle body having a vacuumpick-up opening in a side thereof which is turned away from theconnecting means, the part of the opening in the side of the nozzle bodybeing closed .by an insert the outer area of which is covered by a brushcover. The insert may either be installed as a part removable from thenozzle body or as a permanent part thereof. In certain of the disclosedembodiments the bristles of the brush cover are tilted with respect tothe main extent of the brush cover. The bristles may all be pointed inthe same direction, as for example, in the pull direction of the vacuumnozzle. In another illustrative embodiment, a part of the bristles maybe tilted in the pull direction and a part may be tilted in the pushdirection, so that the nozzle picks up lint, dirt and the like in bothdirections of its travel. The nozzle of the invention may also bepivotally connected with the vacuum pipe of a vacuum cleaner, and mayinclude a pivotally mounted skirt which defines the vacuum area incommunication with the vacuum port of the nozzle in all possiblepositions of tilting of the nozzle about its pivotal connection.

9 Claims, 14 Drawing Figures PAIENTED SEP 1 0 1914 saw a or 7 Pmmmsmmm3333.962, SHEET ME 7 FIG. 6 g

FIG.7 I

PATENTEDSEF 1 01914 sum 80$ 7 v NOZZLE FOR VACUUM CLEANER This inventionrelates to a nozzle for a vacuum cleaner; more particularly it relatesto a nozzle of the type indicated provided with an insertprovided' withan outer surface in the form of a brush.

Nozzles which serve as supplemental cleaning tools for vacuum cleanersand which are adapted to be connected to the vacuum pipe of the cleanerare known to the art. Such nozzles have a connecting piece such as asleeve adapted to be joined to the suction pipe of the cleaner, suchconnecting piece being joined to a body having an opening in one sidethereof forming a nozzle. Such nozzles, which have either a wide or athin nozzle opening, perform very well in gathering loose dirt and dustparticles. They do not, however, perform well in removing fine threads,lint, or the like from a carpet.

This invention has among its objects the provision of a nozzle forvacuum cleaners which not only removes loose dirt particles withoutdifficulty, but also removes small and fine foreign objects and lintthat adhere to textile surfaces, as for example, a carpet, upholstery,and the like.

This object is achieved by a nozzle for vacuum cleaners that includes aconnecting piece for connection. to a vacuum pipe and a nozzle bodyconnected to. the connecting piece, such body having a side that isturned away from the connecting piece, is open, a part of the open sideof the nozzle body being closed by means of an insert, the outer surfaceof which is covered with a brush. Such insert can be removable, or itmay be firmly affixed to the nozzle body. Such brush is advantageouslymade out of a flat, flexible holder, like a textile fabric orthe like,in which short bristles are arranged close to one another.Advantageously, these bristles are all tilted or pointed in the samedirection. The best results can be obtained with such a brush if thenozzle insert is so made and installed that the bristles all point inthe direction of pulling of the nozzle as it is applied, for example, toa rug, an upholstered chair, or the like.

The connecting piece can be integral with the nozzle body or it can beso connected thereto as to be firmly or detachably mounted on the nozzlebody. In order to increase the efficiency of the nozzle and in order tobe able to hold it in the best vacuuming position, the connecting piecemay be built in the form of a rotating joint; alternatively, the activecomponents of the connecting piece may be so constructed as to tilt thebrush, the nozzle having a movable flap or shutter which is soconstructed that it limits the vacuum area or the width of the vacuumslit of the nozzle appropriately for every degree of tilt of the nozzle.

The accompanying drawings, which form a part of the disclosure of thebrush of the invention, show a number of non-limiting illustrativeembodiments of nozzles in accordance with the invention.

In the drawings:

FIG. I is a view in side elevation of a nozzle with an exchangeableinsert;

FIG. 2 is a view in bottom plan of a nozzle with an elongated insertfitted to the nozzle body;

FIG. 2a (sheet 7 of the drawings) is a view in bottom plan of a nozzlewith a different shape of nozzle insert;

FIG. 3 is a view in top plan of the nozzle shown in FIG. 1;

FIG. 4 is a view in central vertical section through the nozzle shown inFIG. I, the section being taken along the line CC of FIG. 6;

FIG. 5 is a fragmentary view in section through the brush of FIG. 4, thesection being taken along the line 'D*D- of that Figure;

FIG. 6 is a view in vertical section taken along the line AA of FIG. 4;

FIG. 7 is a view in horizontal section taken along the line B-B of FIG.6;

' FIG. 8 is a view in side elevation ofa further embodiment of nozzle inaccordance with the invention. such nozzle having a firmly attachedbrush insert;

FIG. 9is a view in central vertical section taken in a manner similar tothe section of FIG. 4 through the nozzle of FIG. 8;

FIG. 10 is a view in side elevation of a still further embodiment ofnozzle, such nozzle being provided with a detachable connecting piece;

FIG. 11 is a view in side elevation of a nozzle with a rotatingconnecting piece;

FIG. 12 is a view in side elevation of a nozzle provided with a flap tolimit the vacuum area and with a vacuum slit at an arbitrary tilt of thenozzle body; and

FIG. 13 is a view similar to that of FIG. 12 which is provided with ashutterrather than a flap as in the embodiment of FIG. 12.

In FIGS. 13, inclusive, there is shown a basic form of the nozzleaccording to the invention. Such nozzle,

which corresponds basically to the already known auxiliary nozzles forvacuum cleaners, is provided with an inclined connecting piece 2 whichis joined to an elongated, relatively'wide nozzle body 3. A nozzleinsert 4' is mounted in the nozzle body, the insert being preferablycovered with a flat brush cover 5' by means of which dirt particles aredisengaged from the area being cleaned, the particles thenbeingvacuumed. The insert 4 in this embodiment is a part of the openside of the nozzle body which lies opposite the connecting piece 2.

The insert can be mounted in the nozzle body so as to either beremovable therefrom or to be permanently attached thereto. In eithercase, the basic form of the nozzle body is the same.

In FIGS. l-7, inclusive, of the drawing the nozzle 1 is shown in thevarious embodiments with an exchangeable insert 4. The nozzle insert 4is in the form of a framed brush component, which can be easily removedfrom and replaced upon the nozzle body. A flat, flexible holder made,for example, out of a textile fabric or the like which is covered withbristles forms the brush cover 5.- This brush cover, which is supportedupon an elastic upholstery liner, is placed on the bottom surface of thefloor plate 6 of a cup-like body. The upper edge 7 of the entirecircumference of the sidewall is toothed. The edge section of the brushcover 5 is put around the elevated toothed edge 7 of the cupshaped body.From above, that is to say, opposite the brush cover, an upper part 8that is in the form of a cap is disposed with its side walls surroundingthe elevated edge 7 of the floor plate 6 to press downwardly the edgesection of the brush cover 5 which overlies edge 7. On the inner side ofthe side walls of the part 8 there are provided ribs 9 which arestaggered in relation to the teeth of the edge 7 of the floor plate 6.After the mounting of the upper, lid part 8, these ribs 9 fit into thegaps of the teeth at the toothed edge 7 and grip the edge section of thebrush cover 5 that lies in between such parts. In this manner, brushcover 5, floor plate 6, and the upper part 8 of the insert 4 are firmlyconnected.

The floor plate which is covered with the brush cover may also beconnected firmly with the upper part of the insert, as for example, withsome kind of interlocking clamping parts15 and 16 (FIG. 6) or the likethat are generally known in the art. These also serve the function ofstiffening the insert.

The middle piece of the upper side of the upper, lid part 8, is retainedby means of a latch means 10. In the embodiment shown, the basic form ofthis latch 10 is a long, rectangle. Of course, it can have any othershape as well. The latch means 10 is secured removably in the space 12in the upper side of the nozzle body 3. An advantageous removableconnection can be achieved by means of engaging notchings andprojections on the respective parts. An example of this is shown inFIGS. 4 and 7. In the middle of the opposing widths of the latch means10, a wedge-shaped notching 11 is provided from the outside. The space12 in the upper side of the nozzle body 3 is limited by side walls 13that extend downwardly. At the open end of these side walls 13,corresponding to the notchings 11, there are provided projections on theinner side, that is, opposing each other, also preferably wedge-shaped.The downwardly projecting side walls 13 are slightly elastic, so thatthey are pressed somewhat to the outside when the latch means 10 isbeing inserted, whereby the projections 14 slide along the outer side ofthe long shaped walls of the latch means 10. As soon as the projections14 have reached the notchings 11, they lock with them and lock thenozzle insert 4 in the nozzle body 3. By means of pressure from above onthe latch means 10, the elastic side walls 13 are sprung apart from eachother by the slope of the wedge-shaped notchings 11; the projections 14slide out'of the notchings and release the insert 4. Of course, otherremovable connections are possible.

A simpler embodiment is shown in FIGS. 8 and 9 in which the insert 4a isbuilt into the nozzle body 3a. Here there is no upper part of the insertthat is shaped as a lid and also no latching means. The brush cover 5awhich is placed upon the floor plate 6a is held by means of thelid-shaped nozzle body 3a. The assembly thus basically corresponds tothe one with the exchangeable insert 4. The brush cover 5a which issupported by an elastic upholstery liner, or which is lined, has itsedge section placed around the elevated edge 7a of the floor plate 6aand over the toothed fringe of the edge 7a. The nozzle body 3a is shapedon the side opposing the brush cover 5a in such a way that the sides S,S which are tilted downwards like lids, surround the elevated edge 7a ofthe floor plate 6a and thus surround the edge section of the brush cover5a that lies in between. From the inner side of the side walls S, Sthere project thin ripples 9a which point inwardly. These ripples arestaggered in relation to the teeth of the toothed edge of the floorplate 6a. When the nozzle body 3a is placed on the floor plate, theripples 9a interlock with the tooth spaces at the toothed edge and clampthe edge section of the brush cover. In this manner, the insert 4a andthe nozzle body 3a form a unit.

By means of this manner of clamping, in the exchangeable version, andalso in the firmly built-in insert, there is no necessity for anyscrewing together or adhesion of the parts that are to be connected witheach other, so that the assembly of the parts may be performed fullyautomatically and thus very economically.

It is desired to point out that this clamping can be satisfactorilyobtained in an even simpler way (not shown), and also fullyautomatically. Here the elevated edge of the floor plate 6 or 6a ends ina sharp edge, which points up vertically or is slightly pointedoutwards. Around the outer side of the elevated edge of the floor plateand also around the sharp edge of it there is placed the edge section ofthe brush cover, the floor plate also being provided preferably with theresilient support or lined upholstery, as in the case above. Whenassembling the lid-shaped part of the exchangeable insert 9 or of thelid-shaped nozzle body, its side parts surround the edge section of thebrush cover, and its upper side presses the brush cover from above ontothe sharp edge and clamps it firmly.

The insert 4 or 4a in the embodiments shown preferably occupies thewhole width of the front area of the open side of the nozzle body 3 or3a. Behind the insert there is the vacuum area or vacuum part 17, or17a, which leads into the vacuum opening of the connecting piece 2, 2a.The connecting piece is connected to a vacuum pipe (not shown) of thevacuum cleaner. By sliding the nozzle to and fro, the dirt particleswhich are loosened or disengaged by the brush cover are then removed byvacuum.

The nozzle, according to the invention, is especially suitable for abrush cover made out of a Hat, flexible holder, which is covered withbristles that are arranged close to each other and which are all tiltedin the same direction. The direction of tilting of the bristles extendsat an angle to the vertical axis of the insert and the tips pointtowards the vacuum port, that is, in the direction of pulling of thenozzle, which is determined by the tilted connecting piece. When thevacuum cleaner or the vacuum pipe is being pulled with the nozzle, thebristles also collect the finest dirt particles and foreign objects thatare sticking to the ground and sweep them into bristle spaces of thebrush cover of the nozzle insert. As soon as the nozzle is pushed, allthe collected foreign bodies and dirt particles are released from thespaces in between the bristles and emerge, in a loosened condition,immediately in front of the vacuum area or the vacuum port 17, 17a,where they are swiftly vacuumed into the vacuum opening of theconnecting piece. In this way, one can obtain, by easy pulling andpushing of the vacuum cleaner with the connected nozzle, an optimalcleaning of carpets, upholstery, blankets, wall-hangings and the like.In such construction, the brush cover hereby cleans itself again andagain.

In a nozzle insert which is equipped with such tilted bristles on abrush cover, other possible and advantageous embodiments of this insertare possible. It can, for example, envelope the entire nozzle openingand can have in its middle an elongated vacuum port (FIG. 2a). The brushcover 5 and 5a is arranged either around or along the two longitudinalaxial sides of the vacuum port 17 either in one line or in dividedstrips. The bristles of the brush cover are preferably tilted with theirtips towards the vacuum port 17. In this manner, the dirt particles aretaken up both when pulling and pushing the nozzle and are againreleased, as in the two different movements one part of the bristle tipsof the brush cover are always pointed for reception (taking up) of dirtand another part of the same are pointed for releasing dirt. The optimalvacuum procedure thus is obtained with each and every movement of thenozzle. Such a nozzle insert can be built either in an exchangeableversion of it can be permanently built-in.

FIG. shows a changed embodiment of the nozzle itself. Such nozzleconsists of a nozzle body 18 with a firmly installed insert 19. In theback part of the nozzle body its upper side is provided with a spacemember 20, which is aligned with the vacuum area or the vacuum port 21.The space member 20 is built so that it fits onto a nozzle 22 which isconnected to the vacuum pipe. Such nozzles, that basically. have thesame form as a connecting piece of the above-mentioned sort, are knownand are sold in different shapes as additional parts for vacuumcleaners.

One can easily vacuum and clean reachable areas with a connecting piecethat is rigidly affixed to a nozzle body. But, if the nozzle is to bemoved under fumiture, like cabinets, easy chairs, couches, and the like,in order to vacuum under them, it cannot be done with an inflexiblenozzle. Mostly the vacuum pipe and the connecting piece are too high, sothat-both have to be lowered to a high degree, that is to say, both haveto be moved towards the floor. Thus, however, a rigidly affixed nozzleand thus also the brush cover is tilted upwards by rotation, and theeffective area is elevated out of contact with the area that is to becleaned. In order to avoid this disadvantage, the nozzle body can beflexibly affixed in relation to the connecting piece. The known flaphinges, however, are not suitable for. nozzles that have an insert whichis covered with a brush cover.

When pushing the nozzle forward, the friction of the rough area of thebrush cover on the rough area of the texture to be cleaned, for example,a carpet, is so great that the nozzle tilts towards the flap hinge. Theembodiment of FIG. 11, which incorporates a rotating joint between thenozzle and the connecting piece, overcomes this disadvantage. Thisembodiment is shown with an exchangeable, removable insert. Of course,here also the insert can be firmly built-in. The nozzle body 23 is aclosedin compartment whose back wall 24 runs basically vertically. Inthe upper section of this back wall, a round opening is provided, inwhich fits the front part of the axle-shaped connecting piece 25. Thisfront part is inserted in such a manner into the opening that it cannotbe moved horizontally, but is easily turnable through 360. In thismanner, the vacuum pipe (not shown) can be rotated with the connectingpiece 25, while the nozzle body 23 does not this turning movementrelative to the floor. In order to push the nozzle under a couch or thelike, the vacuum pipe together with the connecting piece 25, forexample, has to be turned through 90 so that this connecting piece liesabout in the same plane as the upper side of the nozzle body 23. Theeffective area of the insert always remains in contact with the areathat is to be cleaned.

A different embodiment, in which the nozzle can be used in differentpositions, is shown in FIG. 12. Here the nozzle body 26 is rigidlyconnected to the connecting piece. The brush cover, which is coveredwith insert 28, is shown rounded to the outside, so that, each time theconnecting piece 27 tilts down, a part of the effective area of thebrush cover touches the area to be cleaned. If, however, the connectingpiece 27 in such anozzle is elevated, thus enlarging the angle betweenit and the area to be cleaned, the vacuum area, that is to say, thevacuum port 29 is enlarged and the vacuum pull no longer concentrates onthe desired area.

To eliminate this disadvantage, the nozzle is equipped with a skirt 30,which defines the vacuum area communicating with the vacuum port 29 atevery desired tilted position of the nozzle. This skirt 30 is made outof a frame that is limited on its sides, and whose side walls 31 areslightly flared out from the back side to the front side, while its backwall 32 is rectangular. Preferably this back wall 32 is slightly tiltedand it corresponds to the back wall 26a of the nozzle body 26. The loweredge 31a of each side wall 31, 31 runs in a bow or arch corresponding tothe insert 28. Each side wall of the skirt 30 is bored at its front sideand, for example, is connected by a screw 33 with the side walls 31 ofthe nozzle body 26. This connection, however, is not rigid but thealigned screws form a turning axle around which the skirt 30 is turnableor pivotable. The area for this turning movement is sufiiciently largeso that the skirt 30 can be moved by its gravity when elevating thenozzle, so that the lower edges 31a of the side walls 31 as well as thelower edge of the back wall 32 of this skirt always lie on the floor.Thus the vacuum area connected to vacuum port 29 is limited on all sidesby the side walls 31a and backwall 32 of the skirt 30, as shown in FIG.12; the vacuum efficiency of the vacuum cleaner is thus concentrated.The skirt 30 adjoining the inner sides of the nozzle body or the outersides of the nozzle body can be arranged in an envelop ing manner.Instead of the screws 33, a different advantageous pivot connection canbe provided.

Instead of the skirt 30, for example, a seesaw-shaped shutter 34 can beused, as is shown in FIG. 13. The nozzle is provided with a connectingpiece 27 and a nozzle body 26 with an insert, the effective area ofwhich is tilted to the outside as in FIG. 12. The shutter 34 envelopesat all sides the side parts of the nozzle body 26. with a small workingspace or play. I

The front side and rear side V and R of the nozzle body and thus thefront side and rear side of the shutter 34 are preferably slightlytilted, so that an opposingangular movement of these adjoining walls canbe achieved without disturbance, as indicated with the arrow P. Theshutter 34 and the nozzle are pivotable at the elongated sides by aturning point that is situated in the middle. The advantage of such aseesaw-shaped shutter 34 is that it cannot get stuck in any position. Bymeans of its form and method of hanging, it has to be held to the floorwith its lower edge 340, so that in every position of the nozzle duringthe vacuuming procedure, it limits the vacuum area connected to the vac-,uum port 29' at all sides, in whatever position it ma Although theinvention is illustrated and described with reference to a plurality ofpreferred embodiments thereof, it is to be expressly understood that itis in no way limited to the disclosure of such plurality of embodiments,but is capable of numerous modification within the scope of the appendedclaims. I

What is claimed is:

l. A nozzle for a vacuum cleaner, comprising a hollow nozzle body havingmeans for connecting the vacuum pipe of a vacuum cleaner thereto, a sideof the nozzle body which is turned away from the vacuum pipe connectingmeans having an opening therein, and an insert in the nozzle bodyclosing a portion of such opening, said insert having a transversebottom plate and upstanding side walls, the outer area of the insertbeing covered with a brush cover which extends across the bottom plateoutwardly thereof and up along the side walls and a lid-shaped upperpart clamping the brush cover downwardly upon the upper edge of the sidewalls of said insert, wherein said insert has a cupshaped body and theupper edges of the side walls have a plurality of sawtooth projections,and the lid-shaped upper part has a downwardly extending skirt which hasa plurality of projections so as to interdigitate with the projectionson the side walls and to clamp the edges of the brush between said skirtand said side walls.

2. A nozzle according to claim 1, wherein the insert is installed so asto be removable from the nozzle body.

3. A nozzle according to claim 1, wherein said projections on said skirtcomprise a plurality of thin radially inwardly-directed ribs on theinner surface of the skirt, said ribs extending parallel to the axis ofthe skirt and being spaced so that when the lid-shaped upper part isassembled on the insert with the upstanding edge portions of the brushcover therebetween, the ribs on the skirt and the saw-tooth projectionson the upper edge of the side walls of the body are interdigitated andclamp the brush cover therebetween.

4. A nozzle according to claim 1, wherein the lidshaped upper part formspart of the insert and comprises an upstanding central stem which isreceived within a critical passage in the body of the nozzle, andcomprising interfitting locking formations on said stem and the wall ofthe passage whereby to hold the insert in place.

5. A nozzle according to claim 4, wherein the passage extends throughthe upper surface of the body, and the upper end of the stem extendsupwardly through the passage to be exposed in the form of a buttonprotruding upwardly from the body of the nozzle.

6. A nozzle according to claim 4, wherein the interlocking formationscomprise radially inwardly generally wedge-shaped projections on theinner wall of the passage through the body of the nozzle, and generallysimilarly shaped radially outwardly open seats in the wall of the stemwhich receive such projections.

7. A nozzle according to claim 1, wherein the insert covers the entirearea of the opening in the nozzle body at the front thereof, andcomprising a nozzle port in the nozzle body behind the. insert, saidnozzle port being connected to the means for connecting a vacuum pipe tothe nozzle body.

8. A nozzle according to claim 1, wherein the brush cover includes aresilient liner underlying the portion of the brush cover which liesoutwardly exposed, the brush having a plurality of closely-spaced shortbristles which are all pointed in the same direction and are tilted in adirection which is disposed at an angle to the longitudinal axis of theinsert.

9. A nozzle according to claim 8, wherein the insert covers the entirearea of the opening in the nozzle body at the front thereof, andcomprising a nozzle port in the nozzle body behind the insert, saidnozzle port being connected to the means for connecting a vacuum pipe tothe nozzle body; and wherein the insert is installed in the body of thenozzle in such manner that the tips of the bristles of the brush coverpoint in the direction of the vacuum port in the direction of pulling ofthe vacuum nozzle in USE.

1. A nozzle for a vacuum cleaner, comprising a hollow nozzle body havingmeans for connecting the vacuum pipe of a vacuum cleaner thereto, a sideof the nozzle body which is turned away from the vacuum pipe connectingmeans having an opening therein, and an insert in the nozzle bodyclosing a portion of such opening, said insert having a transversebottom plate and upstanding side walls, the outer area of the insertbeing covered with a brush cover which extends across the bottom plateoutwardly thereof and up along the side walls and a lid-shaped upperpart clamping the brush cover downwardly upon the upper edge of the sidewalls of said insert, wherein said insert has a cup-shaped body and theupper edges of the side walls have a plurality of sawtooth projections,and the lid-shaped upper part has a downwardly extending skirt which hasa plurality of projections so as to interdigitate with the projectionson the side walls and to clamp the edges of the brush between said skirtand said side walls.
 2. A nozzle according to claim 1, wherein theinsert is installed so as to be removable from the nozzle body.
 3. Anozzle according to claim 1, wherein said projections on said skirtcomprise a plurality of thin radially inwardly-directed Ribs on theinner surface of the skirt, said ribs extending parallel to the axis ofthe skirt and being spaced so that when the lid-shaped upper part isassembled on the insert with the upstanding edge portions of the brushcover therebetween, the ribs on the skirt and the saw-tooth projectionson the upper edge of the side walls of the body are interdigitated andclamp the brush cover therebetween.
 4. A nozzle according to claim 1,wherein the lid-shaped upper part forms part of the insert and comprisesan upstanding central stem which is received within a critical passagein the body of the nozzle, and comprising interfitting lockingformations on said stem and the wall of the passage whereby to hold theinsert in place.
 5. A nozzle according to claim 4, wherein the passageextends through the upper surface of the body, and the upper end of thestem extends upwardly through the passage to be exposed in the form of abutton protruding upwardly from the body of the nozzle.
 6. A nozzleaccording to claim 4, wherein the interlocking formations compriseradially inwardly generally wedge-shaped projections on the inner wallof the passage through the body of the nozzle, and generally similarlyshaped radially outwardly open seats in the wall of the stem whichreceive such projections.
 7. A nozzle according to claim 1, wherein theinsert covers the entire area of the opening in the nozzle body at thefront thereof, and comprising a nozzle port in the nozzle body behindthe insert, said nozzle port being connected to the means for connectinga vacuum pipe to the nozzle body.
 8. A nozzle according to claim 1,wherein the brush cover includes a resilient liner underlying theportion of the brush cover which lies outwardly exposed, the brushhaving a plurality of closely-spaced short bristles which are allpointed in the same direction and are tilted in a direction which isdisposed at an angle to the longitudinal axis of the insert.
 9. A nozzleaccording to claim 8, wherein the insert covers the entire area of theopening in the nozzle body at the front thereof, and comprising a nozzleport in the nozzle body behind the insert, said nozzle port beingconnected to the means for connecting a vacuum pipe to the nozzle body;and wherein the insert is installed in the body of the nozzle in suchmanner that the tips of the bristles of the brush cover point in thedirection of the vacuum port in the direction of pulling of the vacuumnozzle in use.